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Anchorage. The complete assemblage of members and parts, designed to hold in correct position a part of a structure. pp. 1, 31, 32, 37, 42, 49, 85

Anchor sill plate. pp. 8, 9, 10, 17

Base Isolation. The use of vibration isolators (also referred to as 'bearings') to support a structure while allowing it to move sideways independently of the ground wehn subjected to earthquakes.

Bearing seats. A horizontal surface which the bearings are placed upon and which support the ends of a bridge span. p. 78

Bolsters. Reinforced concrete elements or member used to support a pier cap bearing or the abutment bridge seat, and which increases the strength of the cap beam. p. 84

Cable restrainers. Cables used to tie bridge girders between adjacent spans. pp. 75, 76

Cap beam. The part of a bridge that sits on top of the columns and supports the span. pp. 68, 76, 82

Carbon fiber wrap/sheets. Thread-like strands of pure carbon bound in a plastic resin matrix to form a strong reinforcing material. pp. 24, 26, 68

Cement plaster (stucco). Material that provides a durable cement-based finish on residential and other low-rise construction. p. 38

Chord. A continuous steel member used to tie floor and/or roof systems to the load bearing walls of a building. p. 14

Compression struts. Structural support members used to sustain compression and provide support. p. 43

Corbel. A brick, block, or bracket that projects from the face of a wall and supports an overhanging member. pp. 31, 35

Cornice. A horizontal molded projection that crowns or completes a building or wall. pp. 31, 35

Cripple wall. A short stud wall that extends from the base of a crawlspace foundation to carry the floor joists. pp. 10, 17

Cross bracing. Horizontal or diagonal elements between vertical supports used to provide lateral bracing of structures. pp. 11, 20, 29, 98

Crosswalls. Walls designed to absorb energy and limit displacements of long walls due to earthquakes. pp. 8, 9, 22

Dampen. To restrain or deaden vibration. p. 28

Dampers. Commonly called fluid viscous dampers, they act as shock absorbers by absorbing some of an earthquake's ground movement. pp. 9, 29, 99

Diaphragm. Floor and/or roof deck systems that carry lateral forces across the building to supporting structural elements. pp. 1, 5, 12, 77

Ductility. The property of a material to absorb large inelastic deformations before failing. p. 4

Epoxy anchor. A threaded rod inserted into a drilled hole filled with epoxy or another chemical resin to secure the rod. pp. 25, 35

Epoxy grout. A thin mortar used to fill cracks and crevices in concrete or masonry. p. 19

Expansion joint. For bridges and other structures, it is a joint between two parts of a structure that allows for expansion of both parts due to temperature changes. For utilities, such as pipelines, it is a flexible connector that allows for movement during an earthquake without breaking. pp. 81, 92

Girder. Steel, wood, or reinforced concrete beam used as a main horizontal support in a building or bridge. pp. 76,77, 78, 81, 82

Inelastic deformation. Occurs when an element deforms as force is applied, but does not return to its original shape after the force is removed. p. 4

Isolation bearings. Bearings in buildings or bridges that absorb lateral movements and isolate them from the rest of the structure, reducing the impact to the structure and assisting it to move as a unit. pp. 28, 80

Lock-up device. A piece of equipment connecting bridge spans that allows for normal expansion and contraction but increases structural integrity by 'locking up' when the structure is subjected to seismic forces. p. 79

Parapet. A wall placed at the edge of a roof to create a firebreak between buildings and prevent people from falling. pp. 9, 31, 34

Pedestal. An architectural support or base for a column. p. 46

Prestress. To strengthen concrete by compressing it so it will counteract tension forces resulting from earthquakes. p. 83

Reinforced concrete. Concrete in which steel bars or wires are embedded to increase the strength of concrete in tension, shear, and bending. pp. 4, 8, 9, 12, 34, 76, 84,

Reinforced masonry. Cast or formed bricks or blocks in which steel bars or wires are embedded. pp. 1, 4, 7, 12, 18, 19, 24, 25, 30, 31, 45

Seismic forces. Forces created by ground movement during an earthquake. pp. 11, 38, 50, 69, 75, 99

Shear. Stress in which opposing forces act on an object, causing two parts or layers to slide against each other. pp. 3, 4, 15, 66, 70, 71, 73, 75

Shear anchors. Metal rods with threaded ends that are used to prevent sliding between the floor/roof systems and walls of a building. pp. 12, 14, 18, 19, 34

Shear blocks. Reinforced concrete blocks installed on the cap beams of bridges to prevent girders from moving sideways at their bearings. pp. 75, 76

Shear walls. Vertical walls made from reinforced concrete, reinforced masonry or wood stiffen buildings and help structures resist sideways earthquake forces. pp. 5, 8

Shotcrete. Consists of concrete that can be sprayed on specially designed walls and other surfaces. pp. 8, 25, 34, 38

Simply supported span. A span that must be supported on both ends to prevent collapse. p. 81

Snubbers. Devices that limit displacements of vibrating equipment during earthquakes to reduce or prevent damage. p. 50

Soft story condition. A floor level that has stiffness significantly less than the story above it, such as buildings with large foyers or open spaces on the first floor. pp. 20, 21

Steel jackets. A steel casing that is welded or bolted around a concrete column to increase strength. pp. 68, 69

Substructure. The foundation elements that support the building or bridge. p. 65

Superstructure. The parts of a building or bridge above the foundation. p. 75

Tendon. A high-strength steel cable used to prestress or connect structural elements. p. 83

Tension ties. Steel anchor bolts used to strengthen connections between the roof or floor and the walls. pp. 12, 14, 18, 19, 34

Unseating. To dislodge an element from the bearing or member supporting it. p. 76

Vibration isolator. A device, such as a shock absorber or spring, that prevents transfer of vibrations from one element to another. pp. 28, 50



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